The present disclosure relates to a motor driving device and a motor system, and relates, for example, to a braking technique at the time of stopping the rotation of a motor.
Japanese Unexamined Patent Application Publication No. 2004-297904 discloses a direct current motor driving system which can detect a current flowing through a coil without using a shunt resistor. Specifically, there are provided MOS transistors for current detection, in a manner corresponding to output MOS transistors of phases of the low side. The source and the gate of the MOS transistor for current detection of each phase are coupled respectively to the source and the gate of the output MOS transistor of a corresponding phase.
Japanese Unexamined Patent Application Publication No. 2017-85799 discloses a motor driving device which drives a three-phase motor using a sine wave. In this motor driving device, one cycle (an electrical angle of 360 degrees) of the sine wave is divided into periods of 60 degrees, a terminal voltage of one phase of the three phases is fixed to a power supply voltage or a ground power supply voltage, in each period, and terminal voltages of the remaining two phases are controlled by a PWM signal.